1. Field of the Invention
The present invention concerns automatic flow controllers and in particular their energy-conservation features.
2. Background Information
Automatic flow-control systems have become increasingly prevalent, particularly in public rest-room facilities. Automatic faucets and flushers contribute to hygiene, facility cleanliness, and water conservation. In such systems, object sensors detect the user and operate a flow-control valve in response to user detection. In the case of an automatic faucet, for instance, presence or motion of a user""s hands in the faucet""s vicinity normally results in flow from the faucet. In the case of an automatic flusher, detection of the fact that a user has approached the facility and then left is typically what triggers flushing action.
Although the concept of such object-sensor-based automatic flow control is not new, its use was quite limited until recently. One reason for its popularity increase in recent years is the recent availability of battery-powered conversion kits. These kits make it possible for manual facilities to be converted into automatic facilities through simple part replacements that do not require employing electricians to wire the system to the supply grid. Because of extensive design effort directed to simplifying installation, the installer usually needs only to remove some easily removed parts, install batteries in the conversion kit, and mount the kit in place of the removed parts. The resultant system""s power consumption can be made so modest that it is not unusual for the resultant automatic flow controller to operate more than three years between battery replacement, even though it is typically employed in a high-usage area such as a public rest room.
We have devised a way of simplifying installation even further without, in many cases, adding any additional hardware. We include in the kit a switch to which the kit""s control circuit responds by going into a low-power mode if the switch has remained in its operated state for an extended period of time, such as, say, thirty seconds. In the low-power mode, the control circuit refrains from performing certain high-power functions, such as transmitting sensor radiation or operating a valve. The time delay enables a switch normally to be used for some other purpose, so the switch can be one that would have been provided in any case. If the switch is push-button operated, for instance, its normal use can be to provide a manual-flush capability, since a user will not keep the push button pressed for the extended period needed to place the control circuit into its low-power mode. But packaging used for shipment and storage can be so designed as to keep the push button pressedxe2x80x94and the control circuit in its low-power mode-until the kit is unpacked. Alternatively, the switch can be a reed switch, and a magnet included in the packaging could keep the switch operated.